Yeah, is not good for an investor to keep his seed phrase very secret to an extent that even his loved ones can not even get access to it. Though is good to keep our seed phrase very secret but at least we are suppose to have a trusted person in the family, no matter the family situation. Or better still you can share it to any of your kids you know he or she will never disclose your seed phrase to anyone.
Or you can share it with your wife, because we don't know when the unknown death" will come, Even though some person's would prefer keeping thier seed phrase to themselves without even realizing that death can occur at anytime. and sure, many people died and thier assets is unrealized till today, When they have wife and children at home. It surprises me how someone can be greed to this level.